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This review explores the latest advancements in near-infrared (NIR) imaging technology, detailing its diverse applications such as tracking solvent diffusion in polymers, portable analysis systems in pharmaceuticals, high-speed polymer monitoring, and NIR imaging for fish embryo development research.

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Antibody drug conjugates (ADCs) are an emerging category of biotherapeutic products based on monoclonal antibodies (mAbs) coupled to powerful cytotoxic drugs. The production of ADCs entails the formation of species with different number of conjugates drugs. The heterogeneity of ADCs species add to the complexity originating from the mAbs microvariability. Sheathless capillary electrophoresis-mass spectrometry (sheathless CE-MS) using complementary approaches was used to perform a detail characterization of brentuximab vedotin (Adcetris, Seattle Genetics). Sheathless CE-MS instrument used as nanoESI infusion platform was involved to perform the intact and middle-up analysis in native MS conditions. The nanoESI infusion approaches enabled estimation of the average drug to antibody ratio (DAR) alongside to drug load distribution. Sheathless CZE-MS/MS method developed was used to obtain from a single injection the characterization of the amino acid sequence with complete sequence coverage. In addition glycosylation and drug-loaded peptides could be identified from MS/MS spectra revealing robust information regarding their localizations and abundances. Drug-loaded peptide fragmentation mass spectra study demonstrated drug-specific fragments reinforcing the identifications confidence. Results reveal the ability of sheathless CZE-MS/MS method to characterize ADCs primary structure in a single experiment.

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Antibody drug conjugates (ADCs) are an emerging category of biotherapeutic products based on monoclonal antibodies (mAbs) coupled to powerful cytotoxic drugs. The production of ADCs entails the formation of species with different number of conjugates drugs. The heterogeneity of ADCs species add to the complexity originating from the mAbs microvariability. Sheathless capillary electrophoresis-mass spectrometry (sheathless CE-MS) using complementary approaches was used to perform a detail characterization of brentuximab vedotin (Adcetris, Seattle Genetics). Sheathless CE-MS instrument used as nanoESI infusion platform was involved to perform the intact and middle-up analysis in native MS conditions. The nanoESI infusion approaches enabled estimation of the average drug to antibody ratio (DAR) alongside to drug load distribution. Sheathless CZE-MS/MS method developed was used to obtain from a single injection the characterization of the amino acid sequence with complete sequence coverage. In addition glycosylation and drug-loaded peptides could be identified from MS/MS spectra revealing robust information regarding their localizations and abundances. Drug-loaded peptide fragmentation mass spectra study demonstrated drug-specific fragments reinforcing the identifications confidence. Results reveal the ability of sheathless CZE-MS/MS method to characterize ADCs primary structure in a single experiment.

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A summary of the most recent advances in sample preparation, instrumentation, and data-processing techniques for MALDI-IMS

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Simultaneous, enantiomer-specific identification of chiral molecules in multi-component mixtures is extremely challenging. Many established techniques for single-component analysis fail to provide selectivity in multi-component mixtures and lack sensitivity for dilute samples. Mass spectrometry is chirally blind, and so cannot directly distinguish the two enantiomers of chiral molecules. Here we discuss how enantiomers may be differentiated by Mass Spectrometry correlated with PhotoElectron Circular Dichroism (MS-PECD) using an electron–ion coincidence imaging spectrometer. Following an ionizing circular polarized laser pulse, ions and electrons are detected in coincidence on their respective time- and position sensitive detectors. The MS-PECD asymmetry measured on electrons tagged by the mass of their corresponding parent ion directly reveals that the compound with identified mass is chiral without the need for any prior enantiomeric separation or enantiomer-selective complexation. MS-PECD enables direct enantiomeric excess measurement of multi-component chiral samples in a table-top mass spectrometer.

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Simultaneous, enantiomer-specific identification of chiral molecules in multi-component mixtures is extremely challenging. Many established techniques for single-component analysis fail to provide selectivity in multi-component mixtures and lack sensitivity for dilute samples. Mass spectrometry is chirally blind, and so cannot directly distinguish the two enantiomers of chiral molecules. Here we discuss how enantiomers may be differentiated by Mass Spectrometry correlated with PhotoElectron Circular Dichroism (MS-PECD) using an electron–ion coincidence imaging spectrometer. Following an ionizing circular polarized laser pulse, ions and electrons are detected in coincidence on their respective time- and position sensitive detectors. The MS-PECD asymmetry measured on electrons tagged by the mass of their corresponding parent ion directly reveals that the compound with identified mass is chiral without the need for any prior enantiomeric separation or enantiomer-selective complexation. MS-PECD enables direct enantiomeric excess measurement of multi-component chiral samples in a table-top mass spectrometer.

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Using examples from our analysis of L-carnitine and acyl-L-carnitines, we give specific guidance for the use of mass spectrometry in quantitative analysis, as applied to clinical research and clinical pharmacology. We focus on quantitative accuracy and analytical selectivity as keys to successful implementation of mass spectrometric methods in clinical applications

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Using examples from our analysis of L-carnitine and acyl-L-carnitines, we give specific guidance for the use of mass spectrometry in quantitative analysis, as applied to clinical research and clinical pharmacology. We focus on quantitative accuracy and analytical selectivity as keys to successful implementation of mass spectrometric methods in clinical applications

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Using examples from our analysis of L-carnitine and acyl-L-carnitines, we give specific guidance for the use of mass spectrometry in quantitative analysis, as applied to clinical research and clinical pharmacology. We focus on quantitative accuracy and analytical selectivity as keys to successful implementation of mass spectrometric methods in clinical applications

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Using examples from our analysis of L-carnitine and acyl-L-carnitines, we give specific guidance for the use of mass spectrometry in quantitative analysis, as applied to clinical research and clinical pharmacology. We focus on quantitative accuracy and analytical selectivity as keys to successful implementation of mass spectrometric methods in clinical applications

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A PLS model was built with optimized wavelength variables generated by a competitive adaptive reweighted sampling (CARS) algorithm, enabling the use of handheld NIR spectroscopy to rapidly detect peroxide values in oil.

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A critical review focused on the Raman spectroscopy of carbonaceous materials and of polymer-based nanocomposites that contain carbonaceous (nano) materials as fillers

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A summary of the most recent advances in sample preparation, instrumentation, and data-processing techniques for MALDI-IMS

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Most plants used in traditional Chinese medicine must be processed before their medicinal usage; hence the effective ingredients may differ from those in the freshly harvested plant extracts. In this work, we present a fast and generic approach using sub-2-?m liquid chromatography–time-of-flight–mass spectrometry (sub-2-?m-LC–TOF-MS) coupled with multivariate statistical data analysis to systematically profile ingredient changes between fresh and processed samples of huang jing.

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Quality assurance and quality control (QA/QC) are essential in pharmaceutical manufacturing to ensure compliance with standards like United States Pharmacopoeia <232> and ICH Q3D, as well as FDA regulations. Reliable and user-friendly testing solutions help QA/QC labs deliver precise trace elemental analyses while meeting throughput demands and data security requirements.

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Fossilomics uses MS to extract amino acid sequence information from subpicomole quantities of protein and peptide fragments that remain in certain fossil samples. The sequences are compared to databases and validated with search statistics and high-confidence sequences. The validated sequences can then be used to place the fossils on the evolutionary tree.

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Accurate evaluation of chemical modifications such as asparagine deamidation and aspartic acid isomerization is an essential component of comprehensive characterization of therapeutic monoclonal antibodies (mAbs). When located in the complementarity determining regions (CDRs), these modifications can cause a loss of function, impacting product efficacy and safety, resulting in the designation of the modification as a critical quality attribute. However, artifactual modifications can be introduced by analytical procedures, and distinguishing modifications as either critical quality attributes or method-induced artifacts is an important objective for product development. Conventional peptide mapping coupled with ultrahigh-resolution mass spectrometry offers advanced capabilities for definitive characterization of protein therapeutics. However, experimental conditions such as digestion time and pH can influence the observed level of chemical modifications, usually leading to over-estimation. In this work, a new peptide mapping method was developed specifically for mAb characterization that employs optimal enzyme pH for robustness, but short digestion times and time-course elements to minimize and monitor deamidation/isomerization, respectively, allowing a more accurate assessment of potential CDR sequence liabilities.

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Accurate evaluation of chemical modifications such as asparagine deamidation and aspartic acid isomerization is an essential component of comprehensive characterization of therapeutic monoclonal antibodies (mAbs). When located in the complementarity determining regions (CDRs), these modifications can cause a loss of function, impacting product efficacy and safety, resulting in the designation of the modification as a critical quality attribute. However, artifactual modifications can be introduced by analytical procedures, and distinguishing modifications as either critical quality attributes or method-induced artifacts is an important objective for product development. Conventional peptide mapping coupled with ultrahigh-resolution mass spectrometry offers advanced capabilities for definitive characterization of protein therapeutics. However, experimental conditions such as digestion time and pH can influence the observed level of chemical modifications, usually leading to over-estimation. In this work, a new peptide mapping method was developed specifically for mAb characterization that employs optimal enzyme pH for robustness, but short digestion times and time-course elements to minimize and monitor deamidation/isomerization, respectively, allowing a more accurate assessment of potential CDR sequence liabilities.

Latest:

Accurate evaluation of chemical modifications such as asparagine deamidation and aspartic acid isomerization is an essential component of comprehensive characterization of therapeutic monoclonal antibodies (mAbs). When located in the complementarity determining regions (CDRs), these modifications can cause a loss of function, impacting product efficacy and safety, resulting in the designation of the modification as a critical quality attribute. However, artifactual modifications can be introduced by analytical procedures, and distinguishing modifications as either critical quality attributes or method-induced artifacts is an important objective for product development. Conventional peptide mapping coupled with ultrahigh-resolution mass spectrometry offers advanced capabilities for definitive characterization of protein therapeutics. However, experimental conditions such as digestion time and pH can influence the observed level of chemical modifications, usually leading to over-estimation. In this work, a new peptide mapping method was developed specifically for mAb characterization that employs optimal enzyme pH for robustness, but short digestion times and time-course elements to minimize and monitor deamidation/isomerization, respectively, allowing a more accurate assessment of potential CDR sequence liabilities.

Latest:

Accurate evaluation of chemical modifications such as asparagine deamidation and aspartic acid isomerization is an essential component of comprehensive characterization of therapeutic monoclonal antibodies (mAbs). When located in the complementarity determining regions (CDRs), these modifications can cause a loss of function, impacting product efficacy and safety, resulting in the designation of the modification as a critical quality attribute. However, artifactual modifications can be introduced by analytical procedures, and distinguishing modifications as either critical quality attributes or method-induced artifacts is an important objective for product development. Conventional peptide mapping coupled with ultrahigh-resolution mass spectrometry offers advanced capabilities for definitive characterization of protein therapeutics. However, experimental conditions such as digestion time and pH can influence the observed level of chemical modifications, usually leading to over-estimation. In this work, a new peptide mapping method was developed specifically for mAb characterization that employs optimal enzyme pH for robustness, but short digestion times and time-course elements to minimize and monitor deamidation/isomerization, respectively, allowing a more accurate assessment of potential CDR sequence liabilities.

Latest:

Accurate evaluation of chemical modifications such as asparagine deamidation and aspartic acid isomerization is an essential component of comprehensive characterization of therapeutic monoclonal antibodies (mAbs). When located in the complementarity determining regions (CDRs), these modifications can cause a loss of function, impacting product efficacy and safety, resulting in the designation of the modification as a critical quality attribute. However, artifactual modifications can be introduced by analytical procedures, and distinguishing modifications as either critical quality attributes or method-induced artifacts is an important objective for product development. Conventional peptide mapping coupled with ultrahigh-resolution mass spectrometry offers advanced capabilities for definitive characterization of protein therapeutics. However, experimental conditions such as digestion time and pH can influence the observed level of chemical modifications, usually leading to over-estimation. In this work, a new peptide mapping method was developed specifically for mAb characterization that employs optimal enzyme pH for robustness, but short digestion times and time-course elements to minimize and monitor deamidation/isomerization, respectively, allowing a more accurate assessment of potential CDR sequence liabilities.

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Excited state dynamics provides an intrinsic molecular contrast of samples examined. These dynamics can be monitored by pump probe spectroscopy which measures the change in transmission of a probe beam induced by a pump beam. With superior detection sensitivity, chemical specificity and spatial-temporal resolution, pump probe microscopy is an emerging tool for functional imaging of non-fluorescent chromophores and nanomaterials. This article reviews the basic principle, instrumentation strategy, data analysis methods, and applications of pump probe microscopy. A brief outlook is provided.

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This year’s honoree, Megan Thielges, is a pioneer in the development of vibrational probes for use with 2D IR spectroscopy, to reveal new information about the structures and dynamics of proteins.

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Excited state dynamics provides an intrinsic molecular contrast of samples examined. These dynamics can be monitored by pump probe spectroscopy which measures the change in transmission of a probe beam induced by a pump beam. With superior detection sensitivity, chemical specificity and spatial-temporal resolution, pump probe microscopy is an emerging tool for functional imaging of non-fluorescent chromophores and nanomaterials. This article reviews the basic principle, instrumentation strategy, data analysis methods, and applications of pump probe microscopy. A brief outlook is provided.

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A method is illustrated for the simultaneous analysis of ethyl glucuronide and ethyl sulfate in human urine samples.

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Key Issues: Sampling flexibility of Raman enables in-process analysis of solids, turbid media, liquids, and gases Large volumetric Raman provide representative sampling of heterogenous solids

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The US EPA monitors a variety of chemicals in water that may cause harm to humans or wildlife to minimize exposure.

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With the recent legalization of cannabis in several states, there is a growing need for robust, reliable, and cost-effective analytical methods to facilitate routine testing for potency and contaminants. Here we present an LC–MS/MS method that uses the budget-friendly SCIEX Triple Quad 3500 LC–MS/MS system for the simultaneous detection and quantification of cannabinoids, pesticides, and mycotoxins in cannabis products using the Scheduled MRM algorithm.

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This article reviews recent advances in the application of Transmission Raman Spectroscopy (TRS) to pharmaceutical analysis. The TRS technique overcomes subsampling limitations of conventional Raman spectroscopy and enables rapid non-invasive volumetric analysis of intact pharmaceutical tablets and capsules in a quantitative manner with relevance to quality and process control applications. Although only recently introduced to this area its uptake and the breadth of applications are rapidly growing with regulatory approvals for use of this technology in quality control of manufactured pharmaceutical products recently being granted.